Pizzino (pl. pizzini) is an Italian language word derived from Sicilian language[1] equivalent pizzinu. Despite it generically meaning "small piece of paper", the word is now widely used to refer to small slips of paper that the Sicilian Mafia uses for high-level communications. Sicilian Mafia boss Bernardo Provenzano is among those best known for using pizzini, most notably in his instruction that Messina Denaro become his successor. The pizzini of other mafioso have significantly aided police investigations.[2]

Provenzano used a version of the Caesar cipher, used by Julius Caesar in wartime communications.[1] The Caesar code involves shifting each letter of the alphabet forward three places; Provenzano's pizzini code did the same, then replaced letters with numbers indicating their position in the alphabet. Thus "mia" might become "16124", since m=13+3=16, i=9+3=12, and a=1+3=4. (Note that the alphabet used is the Italian alphabet, which has a slightly different order and number of characters than the Latin alphabet.) It is a very simple and old code, with the only point of difficulty being the initial confusion of the ambiguous role of the various digits as independent or part of two-digit numbers.

For example, one reported note by Provenzano read "I met 512151522 191212154 and we agreed that we will see each other after the holidays..." This name was decoded as "Binnu Riina".[1]

Discovery Channel News quotes cryptography expert Bruce Schneier saying "Looks like kindergarten cryptography to me. It will keep your kid sister out, but it won't keep the police out. But what do you expect from someone who is computer illiterate?"[3]

Italian police got a chance to read many pizzini when close associates of Provenzano turned informant. Once in possession of enough pizzini, police were able to break the code quickly.

A biographer of Provenzano also reports that Provenzano used a more complicated code, yet to be deciphered, which referenced selected words that Provenzano had underlined in his copy of the Bible.